Migrate Search to PostgreSQL Full-Text Search

[Techhackontime999]

Description

Replace the current Redis-based search with PostgreSQL full-text search for better accuracy, relevance ranking, and support for complex queries.

Requirements

• Implement PostgreSQL SearchVector and SearchRank for all searchable models
• Add SearchVectorField to User, Post, and Job models
• Support weighted ranking (name > headline > skills > experience)
• Implement search result highlighting with SearchHeadline
• Add trigram similarity for fuzzy matching (typo tolerance)
• Migrate existing search cache to query-based search
• Add database indexes for search performance
• Benchmark against current implementation

Files to Create/Modify

• linkup/core/search_engine.py - New PostgreSQL search engine
• linkup/core/views.py - Update search view to use new engine
• linkup/users/models.py - Add search_vector field
• linkup/feed/models.py - Add search_vector field
• linkup/jobs/models.py - Add search_vector field
• linkup/scripts/update_search_vectors.py - Management command to rebuild search vectors
• linkup/professional_network/settings/base.py - Add pg_trgm extension

Acceptance Criteria

• Search results are more relevant (ranked by weight)
• Fuzzy matching handles typos
• Search performance is equivalent or better
• Search vectors are updated on content changes